The present invention relates to an automatic chemical analyzing method and apparatus, and more particularly to a multi-item automatic chemical analyzing method and apparatus suitably adapted to measure serum or the like by the photometry.
Many automatic chemical analyzing apparatus in current use, and in particular automatic chemical analyzing apparatus used for clinical tests in hospitals are based on a method in which a certain amount of samples to be measured is extracted into a reaction tube with a reagent added thereto to cause a chemical reaction to make a colorimetric measurement by the use of a spectrophotometer and to provide measurement results which are fed out in terms of concentration of analyzed compositions or in terms of a particular unit. Such an automatic chemical analyzing appatatus has simultaneous test items which differ in number depending upon its model, and many apparatus can analyze one to twenty items with an apparatus with two test items called a two-channel automatic chemical analyzers and an apparatus with six test items called a six-channel automatic analyzers.
The test items treated in a biochemical field at a clinical laboratory amount to several tens kinds of items. However, the test items which are treated in daily routine works and subjected to a frequent test is not so great in number, for example, ten or more. These test items are common with a number of samples, whose treatment is made automatic by the above-mentioned automatic chemical analyzer. In this respect, for the automatic analysis of twelve test items there are required six two-channel automatic chemical analyzer, two six-channel automatic chemical analyzer or one twelve-channel automatic analyzer. Alternatively, the twelve items are sometimes measured, for example, in such a manner that the two-channel automatic chemical analyzer is switched at each end of analysis of two items, or the six-channel chemical analyzing apparatus at each end of analysis of six items. Recently, a number of samples are analyzed at the clinical labortory, where the automatic operation is required for the samples with the result of frequent use of a multi-channel automatic chemical analyzer, for example, such as a sixteen-channel automatic chemical analyzer.
In the above-mentioned prior art, a plurality of two-channel or six-channel automatic chemical analyzers can be used without any item change. For that reason, if a required number of apparatus are installed, they are operated at very poor efficiency with the disadvantageous idling operation of expensive apparatus since the samples are not so great in number for the respective automatic chemical analyzers except for great hospitals, and since the measurements can be completed shortly a day. When one apparatus is used with the items changed, the item changing operation is very sophisticated with much time consumed because of the necessity of changing a number of accessories. This often causes the degradation of efficiency and the consumption of a great amount of reagent at the time of changing the item. For example, the use of the sixteen-channel automatic chemical analyzer allows the simultaneous analysis of a sixteen items and the analysis of almost all of the items requiring the automatic operation without troubles and with very great analyzing capability. However, usual samples, it individually observed, need no test of all of the sixteen items. The ordered test item depends upon the sample, but a number, of samples generally require the measurement with respect to only several items. In this respect, the sixteen-channel automatic chemical analyzing apparatus carries out the analysis of unnecessary that items, and wastes the excessive analyzing reagent in that degree. Recently, a multichannel automatic chemical analyzer is provided with a function of selecting any item to analyze only the necessary test items for each sample for the purpose of eliminating the above-mentioned waste of the reagent and the degradation of efficiency due to the item changing operations. In this case also, an operator must supply the analyzer with information relating to the test items for each sample with the result of the extremely great labor.
An analyzer is also known which includes only one reaction line (meaning a path along which reaction tubes are arranged in a line or a pipe through which samples spaced by bubbles pass) but can make a multi-item (multi-component) measurement. Such a known one-line automatic chemical analyzer is of a type in which each of the samples are successively analyzed in terms of a plurality of specific items, or a type in which the same reaction line is used and all associated samples are first analyzed in terms of one item and then in terms of another item after the end of analysis of the one item. The analyzer of the former type is applicable only to the measurement of a sample such as urine which has common items to be measured. The analyzer of the latter type, on the other hand, has the drawback that the samples must be rearranged at the time of changing the test item with another depending upon the necessity of test of the changed item. It is difficult to make such rearrangement automatic. Further, in the latter analyzer, it takes more time to obtain results about all the test items of one sample if the test items increase in number with respect to the individual samples. Further, the measurement initiation must disadvantageously be delayed until samples having the same test items amount to a certain number because the samples must be rearranged in a sophisticated manner at each time of changing the items.